“Being in this band for the past 12 years has been a true blessing,” read the post. “We’ve gotten to go places we never knew we would. We’ve been able to see and experience things we never imagined possible. We’ve shared the stage with people we admire, people we look up to, and best of all, our friends. And now, like all great things, it has come time for it to end. Thanks for all of your support, and for being part of the adventure. – My Chemical Romance”

The news comes as a heavy hit for legions of fans — known collectively as the MCRmy — who have since started a petition imploring the band to do one last world tour before hanging it up for good.

MCR’s breakup won’t be devastating news for many casual rock fans, some of whom will admit to forgetting the band was even still around. True, the five-piece’s popularity on a grander scale waned in recent years. Final record Danger Days: The True Lives of the Fabulous Killjoys, while well-received by many mainstream critics, reached only No. 8 on the Billboard 200 album chart and didn’t produce the same inescapable batch of alt-rock radio singles as its predecessors. “Sing” was a triumph, getting some Top 40 play and covered on Glee, but only “Na Na Na (Na Na Na Na Na Na Na Na Na)” managed a top 10 appearance on a rock chart, slotting in at No. 10 on Billboard’s Alternative Songs chart.

Though the band might have been perceived by some as having less relevancy in later years, My Chemical Romance will have staying power. In 10 years’ time, MCR will still be remembered whereas some of its faceless rivals on the alt and rock charts (bands like The Dirty Heads and My Darkest Days, for instance) would be lucky to be answers to the rock music portion of trivia night.

My Chemical Romance roared into the American mainstream in late 2004 with “I’m Not Okay (I Promise),” the first single off sophomore album Three Cheers for Sweet Revenge. Buoyed by an intensely catchy chorus and a memorable music video played with reckless abandon on MTV2 and Fuse, the song shot up the alternative charts and established the band as potential hitmakers.